Write the two lines players see in the server list, pick colours or a gradient, and copy the result in the form your server needs: server.properties, Velocity, MiniMessage or & codes.
Line 1
Line 2
Minecraft Server
server.properties
Velocity (velocity.toml)
MiniMessage (MOTD plugins)
& codes (plugins that use &#RRGGBB)
Where to put it
server.properties: replace the whole motd= line with the one from here, save, restart the server. The odd looking codes are the colour sign written so the file can not break it.
Velocity: replace the motd = "..." line in velocity.toml and restart the proxy. Velocity reads MiniMessage, so a gradient is one short tag.
MOTD plugins: most plugins for Paper take MiniMessage or & codes, one line per config line. Use the form the plugin's own config shows.
Good to know
A MOTD has two lines. Text that is too long for a line is cut or moved to the next line by the game.
You can type & codes inside the text: &a for a colour, 7FF99 for a hex colour, &l bold, &o italic, &n underline, &m strike, &k scrambled, &r back to the line's colour. With a gradient the colours come from the gradient and the styles stay.
Hex colours and gradients in server.properties work on Spigot and Paper servers from 1.16 on. A vanilla server shows only the 16 classic colours: tick the box and the gradient is made from the nearest ones.
Centring is done with spaces and is worked out from the letter widths of the game's font. It is an estimate: look at it in your server list once, and add or remove a space if needed. The preview here uses another font and only shows the colours.
Letters outside the basic Latin set are counted as normal width, so centring is less exact with them.
Something wrong or missing here? Tell me, requests decide what I add next. More tools: all tools.